Can I get a Clue?(Diving British Columbia)

Hi Everyone!
This is my first post. I just wanted to get a bit of advice on equipment for freedive spearfishing in COLD water. All of my spearfishing experience so far is in warm water (Hawaii, Mexico, Mediterranean) but I want to start diving here on Vancouver Island. So, at the moment all I have is a 3mm short wetsuit. I have been looking at a 4.3mm full length which I was considering wearing over my shorty. Making for a total of 7.3mm on my core.

My question basically is, with this setup +hood, boots and gloves... will I freeze to death before I hit bottom? How long will my dive likely last before I have to get out?

My maximum(comfortable) dive depth in warm water is approx. 40-45 ft. WEAK, I know, but will it be easier or harder to hit similar depth out here in BC?

Any info, tips, advice or warnings(if necessary) would be greatly appreciated. And if anyone on the island wants another responsible dive partner, message me. I can't wait to F*** up some greenlings!

Thanks a lot for the advice guys. I am going to have to rent a suit and give it a shot. I very much appreciate the welcoming words, Erik. However, I'm not new to Canada, just Vancouver Island. I grew up in Saskatchewan... But I'm finally where I belong, within a stone's throw of the ocean. Thank you, though. That's truly kind of you.

+Keep your eyes out for a post I'll have coming up. I'm currently in the process of building a pole-spear and an Hawaiian sling. Not to jinx myself, but so far they look pretty bad ass.